Sam writes down the numbers $1,$ $2,$ $\dots,$ $315,$ $316,$ $\dots$, $999$.
How many digits did Sam write, in total?
\(1, 2,\dots,315, 316, \dots, 999\)
1 - 9 = 9 digits
10 - 99 = 90 numbers (2 digits each) = 180 digits
100 - 999 = 900 numbers(3 digits each) = 2700 digits
2889 digits in total
+1721 
